AHMEDABAD: A major jail break plan was unearthed in the Sabarmati Central Jail when a 18-foot long tunnel dug by Ahmedabad serial blasts case undertrials was found here, jail officials said on Monday.

"We have found a tunnel dug in the barrack where 14 of the serial bomb blasts accused are lodged. We have registered an FIR and investigation is on," said Superintendent of Sabarmati Central Jail V M Parghi.

Late Sunday night, when jail authorities suspected something amiss in the behaviour of two inmates at barrack number four, called 'Chhota Chakkar', they searched it and found the tunnel dug from inside the barrack, police said.

"Out of 68 accused of the serial bomb blasts case, 14 were lodged in this barrack and we have started probe on since how long digging work was on, how they were digging it and who else are involved," said Parghi without divulging any further details.

On July 26, 2008, twenty near simultaneous bomb blasts across the city had killed 57 people. All the blast accused are lodged in Sabarmati Central Jail as trial has been ordered to be conducted in the premises because of security reasons.

The state home ministry has ordered an enquiry into the incident following a high level meeting held on Monday morning by Minister of State for Home Rajnikant Patel.

Pargi said they have not found any tools but it seems the accused were using dinner plates and wood to dig the tunnel. "They had volunteered for the gardening work around the barrack and under that cover they were dumping the sand extracted from the tunnel into the garden outside," said Jail IG P C Thakur.